Best Free Mastering Plugins in 2022 (Reviews and Comparison)

  • James Parker
  • January 19, 2022

If you have been practicing music production for a while, then you have probably heard a good deal about mastering. “Mixing and mastering” is a common phrase in discussions about music, and it isn’t hard to gather that mastering has something to do with turning your song or album into a finished product. But what actually is mastering? How is it different from mixing? What are the processes that go into it? In this article, we will go over what mastering is and how mastering plugins might differ from mixing plugins. Then, we will take a look at some of the best free mastering plugins you can download to take your music to the next level. Mastering at home can be a challenging pursuit – many hobbyist producers never even attempt it – but it is an extremely useful concept to be familiar with, and a great skill to have. Let’s get started.

Mixing vs. Mastering Plugins

The difference between mixing and mastering can be confusing; why make a distinction when the goal is always to make your project sound good? Put simply, the difference is scope. When you mix a song, you are balancing the levels and equalizers of individual instruments and tracks. When you master, you are turning that song – already fully mixed – into a finished project. This means that you will be making changes to the entire project, be it a song or a full album, without adjusting the individual components. While some plugins can be used for either process, there are some plugins that are used mainly for mastering rather than mixing and vice versa. One common example of a mastering plugin you wouldn’t typically use during the mixing stage is a limiter. Similar to a compressor, a limiter allows you greater freedom in tweaking the dynamic range and volume of audio. But unlike a compressor, limiters place a hard cap on audio crossing a certain volume threshold, allowing you to make your project louder without causing audio clipping or distortion. Thus, limiters are a common tool in the mastering stage. 

In short: mixing is adjusting the relationships between tracks, while mastering is making broad changes to the finished product, whether that involves making it fit in with other songs on an album or simply creating a polished single.

COMPARISON CHART

IMAGE PRODUCT
loudmax 1. Loudmax
  • Simple to use
  • Clear sound
  • Very low CPU usage
CHECK PRICE
span 2. SPAN
  • Great variety of options
  • Clear interface
  • Great tool for getting better at mastering
CHECK PRICE
Waves 3. BL Waves – Blue Lab
  • Cool to look at
  • Easy to use
  • Useful for getting an idea of your mix/master
CHECK PRICE
limiter 4. Limiter No6
  • Great range of uses
  • Organized interface
  • Clear sound
CHECK PRICE
clip 5. LVC-Audio – ClipShifter
  • Versatile functionality
  • Clean UI
  • Free version is still capable
CHECK PRICE

1. Loudmax

loudmax

Specification

PriceFree
VersionsLatest full version is free
CompatibilityWindows, Mac, Linux; works with most DAWs
System requirementsVST2/VST3/AUP – 32 or 64 bit Windows or OSX, 32 bit linux

Loudmax is a free limiter plugin intended to do just what its name suggests. If you want a simple limiter to boost the loudness of your project, this one is a great place to start. The first thing you will notice when you open it up is a very simple interface without many controls. Given its intended function, this is not really much of a downside, and it makes using the plugin a breeze. To increase the volume of your track, lower the threshold slider in Loudmax. This will lower the volume at which audio will be limited, allowing you to increase volume without encountering clipping. This plugin does a good job compared to other free limiters. Play with the sliders to make sure you don’t distort your audio too much or end up with an overly compressed song. If you compress or limit too much, you will be left without much dynamic range, which can make your mix sound flat.

PROS

  • Simple to use
  • Clear sound 
  • Very low CPU usage

CONS

  • Limited controls
  • Can’t handle some tracks
  • Bare-bones interface

If you need a solid free limiter or you just want to explore what a limiter can do, Loudmax is a great free option. It gives you everything you need for basic limiting and nothing more. It will not perform quite as well as some fancier paid plugins, but it is excellent for what it is. Its incredibly low CPU load is also a great bonus.

2. SPAN

span

Specification

PriceFree
VersionsLatest full version is free; paid version SPAN Plus also available
CompatibilityWindows, Mac; works with most DAWs
System requirementsWindows – XP or later
Mac – 10.11 or later

Voxengo’s SPAN plugin is a spectrum analyzer. Unlike a limiter, a spectrum analyzer plugin does not alter the sound of your song at all. Instead, it is meant to give you information about your mix or master. SPAN will provide you with a visual similar to what you would see in an equalizer plugin. But instead of a simplified frequency chart, this plugin will give you incredibly detailed information about the shape of your project. It will also allow you to adjust a wide variety of settings and parameters to zero in on the information you want. This plugin will take some time to learn, but if you want to get better at making purposeful decisions and learn to master your own music, the time investment will be worth it.

PROS

  • Great variety of options
  • Clear interface
  • Great tool for getting better at mastering

CONS

  • Steep learning curve
  • Has fewer features than “plus” version

SPAN is worth downloading for anyone seeking to get into mastering. If you take the time to learn how to use it and what you should be looking for, you can be sure that you will get better at mixing and mastering in the process. It includes a staggering amount of functionality for a free plugin, and many home producers prefer it to popular, more expensive analyzers.

3. BL Waves – Blue Lab

Waves

Specification

PriceFree
VersionsLatest full version is free
CompatibilityWindows, Mac; works with most DAWs
System requirementsMac OS X 10.9 or later (limited Catalina support)
Windows 7 or later
Graphics card compatible with OpenGL
Formats: AU / VST / VST3 / AAX

Blue Lab’s Wav3s is a plugin that allows you to visualize the audio from your project in 3D. It bears some resemblance to spectrum analysis plugins in the sense that it will show you what the sonic shape of your track looks like. Unlike SPAN and other spectrum analyzers, however, it does not include very much in-depth information. In this way, Wav3s is like a very simplified version of SPAN. In addition to simply looking cool, this plugin can be of use as a way to gauge the direction your master is taking without requiring you to have very in-depth knowledge about audio. If SPAN seems too daunting to try out just yet, Wav3s can be a nice way to ease into thinking about the big picture.

PROS

  • Cool to look at
  • Easy to use
  • Useful for getting an idea of your mix/master

CONS

  • Not a ton of practical use
  • Not available for Linux
  • Mostly a novelty for more experienced users

The Wav3s plugin sure is cool to look at, and it can be useful for looking at the big picture when you begin to mix or master a song. Other than that, however, this plugin does not have a ton of functionality. It is totally free, so it is worth checking out. But you may not get much use out of it once you begin to use plugins like SPAN.

4. Limiter No6

limiter

Specification

PriceFree
VersionsLatest full version is free
CompatibilityWindows, Mac; works with most DAWs
System requirementsVST, Windows, 32-bit version (CPU with SSE2 support required)
VST, Windows, 64-bit version
VST, Mac OS X, 32-bit version (Intel)

Next, we have another free limiter. Unlike Loudmax, however, Limiter No6 packs in quite a bit of functionality. While you would likely only use Loudmax to increase the overall volume of your song, Limiter No6 can work as a regular compressor, as well as a few different kinds of limiters. This allows it to work in a wide range of scenarios during both mixing and mastering. If you want a simple place to start with compression and limiting, this plugin has everything you will need. 

PROS

  • Great range of uses
  • Organized interface
  • Clear sound

CONS

  • Not available for 64 bit Mac OS
  • Requires some fine tuning to get clear limiting

Limiter No6 has a great array of features for a free plugin. While the simplicity of Loudmax may be attractive in some situations, it is great to have a capable compressor-limiter combo at your disposal. This one is definitely worth a download.

5. LVC-Audio – ClipShifter

clip

Specification

PriceFree
VersionsFree and paid versions
CompatibilityWindows, Mac; works with most DAWs
System requirementsOSX, AU, VST, VST3, RTAS, AAX
Windows, VST, VST3, RTAS, AAX 32- and 64-bit

Finally, we have ClipShifter, another limiter of sorts. This plugin is quite versatile, as it can be used as a simple compressor, a clipping-style limiter, or a distortion tool. The controls it gives you to walk the line between clear, compressed sounds and intentionally-clipped distortion are useful and fun to play with. While the three limiters we have looked at today can all achieve the same basic result, each has a different focus and flow, so it is worth trying them all out!

PROS

  • Versatile functionality
  • Clean UI
  • Free version is still capable

CONS

  • Slight learning curve
  • Not on Linux

ClipShifter is great fun to play with, and has the widest application of the three limiters listed here. Try playing with it as both a limiter for mastering and a distortion plugin while tracking. 

Conclusion

Mastering can be a hugely daunting task. It is – if you will – difficult to master. But there are so many free tools out there that prevent cost from being a factor. If you put your mind to it, mastering your own music is a great skill to have. So try out some free plugins and start learning to master!